Single-step electrodeposition of superhydrophobic black NiO thin films

Black finished surfaces have extensive applications in many domains, such as optics, solar cells, and aerospace. The single-step electrodeposition of superhydrophobic black NiO films from a dimethyl sulfoxide-based electrolyte is described in this paper. The physicochemical properties of the obtained film were characterized using scanning electron microscopy, X-ray diffraction, and electrochemical tests (electrochemical impedance spectroscopy and potentiodynamic polarization). A rough surface with a low reflection of light was formed after the deposition process that increased the contact angle of water from about 87 degrees (for bare Cu) to 163 degrees (in presence of the black coating), which improved the corrosion resistance of the Cu substrate by about 30%. The formed black NiO film revealed a notably high stability and kept its appearance even after corrosion tests. [GRAPHICS] .